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-rw-r--r--dom/media/MP3FrameParser.cpp591
-rw-r--r--dom/media/MP3FrameParser.h219
-rw-r--r--dom/media/moz.build2
3 files changed, 0 insertions, 812 deletions
diff --git a/dom/media/MP3FrameParser.cpp b/dom/media/MP3FrameParser.cpp
deleted file mode 100644
index 242e3df00..000000000
--- a/dom/media/MP3FrameParser.cpp
+++ /dev/null
@@ -1,591 +0,0 @@
-/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* vim:set ts=2 sw=2 sts=2 et cindent: */
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-#include <algorithm>
-
-#include "nsMemory.h"
-#include "MP3FrameParser.h"
-#include "VideoUtils.h"
-
-
-#define FROM_BIG_ENDIAN(X) ((uint32_t)((uint8_t)(X)[0] << 24 | (uint8_t)(X)[1] << 16 | \
- (uint8_t)(X)[2] << 8 | (uint8_t)(X)[3]))
-
-
-namespace mozilla {
-
-/*
- * Following code taken from http://www.hydrogenaudio.org/forums/index.php?showtopic=85125
- * with permission from the author, Nick Wallette <sirnickity@gmail.com>.
- */
-
-/* BEGIN shameless copy and paste */
-
-// Bitrates - use [version][layer][bitrate]
-const uint16_t mpeg_bitrates[4][4][16] = {
- { // Version 2.5
- { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, // Reserved
- { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0 }, // Layer 3
- { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0 }, // Layer 2
- { 0, 32, 48, 56, 64, 80, 96, 112, 128, 144, 160, 176, 192, 224, 256, 0 } // Layer 1
- },
- { // Reserved
- { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, // Invalid
- { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, // Invalid
- { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, // Invalid
- { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 } // Invalid
- },
- { // Version 2
- { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, // Reserved
- { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0 }, // Layer 3
- { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0 }, // Layer 2
- { 0, 32, 48, 56, 64, 80, 96, 112, 128, 144, 160, 176, 192, 224, 256, 0 } // Layer 1
- },
- { // Version 1
- { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, // Reserved
- { 0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 0 }, // Layer 3
- { 0, 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384, 0 }, // Layer 2
- { 0, 32, 64, 96, 128, 160, 192, 224, 256, 288, 320, 352, 384, 416, 448, 0 }, // Layer 1
- }
-};
-
-// Sample rates - use [version][srate]
-const uint16_t mpeg_srates[4][4] = {
- { 11025, 12000, 8000, 0 }, // MPEG 2.5
- { 0, 0, 0, 0 }, // Reserved
- { 22050, 24000, 16000, 0 }, // MPEG 2
- { 44100, 48000, 32000, 0 } // MPEG 1
-};
-
-// Samples per frame - use [version][layer]
-const uint16_t mpeg_frame_samples[4][4] = {
-// Rsvd 3 2 1 < Layer v Version
- { 0, 576, 1152, 384 }, // 2.5
- { 0, 0, 0, 0 }, // Reserved
- { 0, 576, 1152, 384 }, // 2
- { 0, 1152, 1152, 384 } // 1
-};
-
-// Slot size (MPEG unit of measurement) - use [layer]
-const uint8_t mpeg_slot_size[4] = { 0, 1, 1, 4 }; // Rsvd, 3, 2, 1
-
-uint16_t
-MP3Frame::CalculateLength()
-{
- // Lookup real values of these fields
- uint32_t bitrate = mpeg_bitrates[mVersion][mLayer][mBitrate] * 1000;
- uint32_t samprate = mpeg_srates[mVersion][mSampleRate];
- uint16_t samples = mpeg_frame_samples[mVersion][mLayer];
- uint8_t slot_size = mpeg_slot_size[mLayer];
-
- // In-between calculations
- float bps = (float)samples / 8.0;
- float fsize = ( (bps * (float)bitrate) / (float)samprate )
- + ( (mPad) ? slot_size : 0 );
-
- // Frame sizes are truncated integers
- return (uint16_t)fsize;
-}
-
-/* END shameless copy and paste */
-
-
-/** MP3Parser methods **/
-
-MP3Parser::MP3Parser()
- : mCurrentChar(0)
-{ }
-
-void
-MP3Parser::Reset()
-{
- mCurrentChar = 0;
-}
-
-uint16_t
-MP3Parser::ParseFrameLength(uint8_t ch)
-{
- mData.mRaw[mCurrentChar] = ch;
-
- MP3Frame &frame = mData.mFrame;
-
- // Validate MP3 header as we read. We can't mistake the start of an MP3 frame
- // for the middle of another frame due to the sync byte at the beginning
- // of the frame.
-
- // The only valid position for an all-high byte is the sync byte at the
- // beginning of the frame.
- if (ch == 0xff) {
- mCurrentChar = 0;
- }
-
- // Make sure the current byte is valid in context. If not, reset the parser.
- if (mCurrentChar == 2) {
- if (frame.mBitrate == 0x0f) {
- goto fail;
- }
- } else if (mCurrentChar == 1) {
- if (frame.mSync2 != 0x07
- || frame.mVersion == 0x01
- || frame.mLayer == 0x00) {
- goto fail;
- }
- }
-
- // The only valid character at the beginning of the header is 0xff. Fail if
- // it's different.
- if (mCurrentChar == 0 && frame.mSync1 != 0xff) {
- // Couldn't find the sync byte. Fail.
- return 0;
- }
-
- mCurrentChar++;
- MOZ_ASSERT(mCurrentChar <= sizeof(MP3Frame));
-
- // Don't have a full header yet.
- if (mCurrentChar < sizeof(MP3Frame)) {
- return 0;
- }
-
- // Woo, valid header. Return the length.
- mCurrentChar = 0;
- return frame.CalculateLength();
-
-fail:
- Reset();
- return 0;
-}
-
-uint32_t
-MP3Parser::GetSampleRate()
-{
- MP3Frame &frame = mData.mFrame;
- return mpeg_srates[frame.mVersion][frame.mSampleRate];
-}
-
-uint32_t
-MP3Parser::GetSamplesPerFrame()
-{
- MP3Frame &frame = mData.mFrame;
- return mpeg_frame_samples[frame.mVersion][frame.mLayer];
-}
-
-
-/** ID3Parser methods **/
-
-const char sID3Head[3] = { 'I', 'D', '3' };
-const uint32_t ID3_HEADER_LENGTH = 10;
-const uint32_t ID3_FOOTER_LENGTH = 10;
-const uint8_t ID3_FOOTER_PRESENT = 0x10;
-
-ID3Parser::ID3Parser()
- : mCurrentChar(0)
- , mVersion(0)
- , mFlags(0)
- , mHeaderLength(0)
-{ }
-
-void
-ID3Parser::Reset()
-{
- mCurrentChar = mVersion = mFlags = mHeaderLength = 0;
-}
-
-bool
-ID3Parser::ParseChar(char ch)
-{
- switch (mCurrentChar) {
- // The first three bytes of an ID3v2 header must match the string "ID3".
- case 0: case 1: case 2:
- if (ch != sID3Head[mCurrentChar]) {
- goto fail;
- }
- break;
- // The fourth and fifth bytes give the version, between 2 and 4.
- case 3:
- if (ch < '\2' || ch > '\4') {
- goto fail;
- }
- mVersion = uint8_t(ch);
- break;
- case 4:
- if (ch != '\0') {
- goto fail;
- }
- break;
- // The sixth byte gives the flags; valid flags depend on the version.
- case 5:
- if ((ch & (0xff >> mVersion)) != '\0') {
- goto fail;
- }
- mFlags = uint8_t(ch);
- break;
- // Bytes seven through ten give the sum of the byte length of the extended
- // header, the padding and the frames after unsynchronisation.
- // These bytes form a 28-bit integer, with the high bit of each byte unset.
- case 6: case 7: case 8: case 9:
- if (ch & 0x80) {
- goto fail;
- }
- mHeaderLength <<= 7;
- mHeaderLength |= ch;
- if (mCurrentChar == 9) {
- mHeaderLength += ID3_HEADER_LENGTH;
- mHeaderLength += (mFlags & ID3_FOOTER_PRESENT) ? ID3_FOOTER_LENGTH : 0;
- }
- break;
- default:
- MOZ_CRASH("Header already fully parsed!");
- }
-
- mCurrentChar++;
-
- return IsParsed();
-
-fail:
- if (mCurrentChar) {
- Reset();
- return ParseChar(ch);
- }
- Reset();
- return false;
-}
-
-bool
-ID3Parser::IsParsed() const
-{
- return mCurrentChar >= ID3_HEADER_LENGTH;
-}
-
-uint32_t
-ID3Parser::GetHeaderLength() const
-{
- MOZ_ASSERT(IsParsed(),
- "Queried length of ID3 header before parsing finished.");
- return mHeaderLength;
-}
-
-
-/** VBR header helper stuff **/
-
-// Helper function to find a VBR header in an MP3 frame.
-// Based on information from
-// http://www.codeproject.com/Articles/8295/MPEG-Audio-Frame-Header
-
-const uint32_t VBRI_TAG = FROM_BIG_ENDIAN("VBRI");
-const uint32_t VBRI_OFFSET = 32 - sizeof(MP3Frame);
-const uint32_t VBRI_FRAME_COUNT_OFFSET = VBRI_OFFSET + 14;
-const uint32_t VBRI_MIN_FRAME_SIZE = VBRI_OFFSET + 26;
-
-const uint32_t XING_TAG = FROM_BIG_ENDIAN("Xing");
-enum XingFlags {
- XING_HAS_NUM_FRAMES = 0x01,
- XING_HAS_NUM_BYTES = 0x02,
- XING_HAS_TOC = 0x04,
- XING_HAS_VBR_SCALE = 0x08
-};
-
-static int64_t
-ParseXing(const char *aBuffer)
-{
- uint32_t flags = FROM_BIG_ENDIAN(aBuffer + 4);
-
- if (!(flags & XING_HAS_NUM_FRAMES)) {
- NS_WARNING("VBR file without frame count. Duration estimation likely to "
- "be totally wrong.");
- return -1;
- }
-
- int64_t numFrames = -1;
- if (flags & XING_HAS_NUM_FRAMES) {
- numFrames = FROM_BIG_ENDIAN(aBuffer + 8);
- }
-
- return numFrames;
-}
-
-static int64_t
-FindNumVBRFrames(const nsCString& aFrame)
-{
- const char *buffer = aFrame.get();
- const char *bufferEnd = aFrame.get() + aFrame.Length();
-
- // VBRI header is nice and well-defined; let's try to find that first.
- if (aFrame.Length() > VBRI_MIN_FRAME_SIZE &&
- FROM_BIG_ENDIAN(buffer + VBRI_OFFSET) == VBRI_TAG) {
- return FROM_BIG_ENDIAN(buffer + VBRI_FRAME_COUNT_OFFSET);
- }
-
- // We have to search for the Xing header as its position can change.
- for (; buffer + sizeof(XING_TAG) < bufferEnd; buffer++) {
- if (FROM_BIG_ENDIAN(buffer) == XING_TAG) {
- return ParseXing(buffer);
- }
- }
-
- return -1;
-}
-
-
-/** MP3FrameParser methods **/
-
-// Some MP3's have large ID3v2 tags, up to 150KB, so we allow lots of
-// skipped bytes to be read, just in case, before we give up and assume
-// we're not parsing an MP3 stream.
-static const uint32_t MAX_SKIPPED_BYTES = 4096;
-
-enum {
- MP3_HEADER_LENGTH = 4,
-};
-
-MP3FrameParser::MP3FrameParser(int64_t aLength)
-: mLock("MP3FrameParser.mLock"),
- mTotalID3Size(0),
- mTotalFrameSize(0),
- mFrameCount(0),
- mOffset(0),
- mLength(aLength),
- mMP3Offset(-1),
- mSamplesPerSecond(0),
- mFirstFrameEnd(-1),
- mIsMP3(MAYBE_MP3)
-{ }
-
-nsresult MP3FrameParser::ParseBuffer(const uint8_t* aBuffer,
- uint32_t aLength,
- int64_t aStreamOffset,
- uint32_t* aOutBytesRead)
-{
- // Iterate forwards over the buffer, looking for ID3 tag, or MP3
- // Frame headers.
- const uint8_t *buffer = aBuffer;
- const uint8_t *bufferEnd = aBuffer + aLength;
-
- // If we haven't found any MP3 frame data yet, there might be ID3 headers
- // we can skip over.
- if (mMP3Offset < 0) {
- for (const uint8_t *ch = buffer; ch < bufferEnd; ch++) {
- if (mID3Parser.ParseChar(*ch)) {
- // Found an ID3 header. We don't care about the body of the header, so
- // just skip past.
- buffer = ch + mID3Parser.GetHeaderLength() - (ID3_HEADER_LENGTH - 1);
-
- if (buffer <= ch) {
- return NS_ERROR_FAILURE;
- }
-
- ch = buffer;
-
- mTotalID3Size += mID3Parser.GetHeaderLength();
-
- // Yes, this is an MP3!
- mIsMP3 = DEFINITELY_MP3;
-
- mID3Parser.Reset();
- }
- }
- }
-
- // The first MP3 frame in a variable bitrate stream can contain metadata
- // for duration estimation and seeking, so we buffer that first frame here.
- if (aStreamOffset < mFirstFrameEnd) {
- uint64_t copyLen = std::min((int64_t)aLength, mFirstFrameEnd - aStreamOffset);
- mFirstFrame.Append((const char *)buffer, copyLen);
- buffer += copyLen;
- }
-
- while (buffer < bufferEnd) {
- uint16_t frameLen = mMP3Parser.ParseFrameLength(*buffer);
-
- if (frameLen) {
- // We've found an MP3 frame!
- // This is the first frame (and the only one we'll bother parsing), so:
- // * Mark this stream as MP3;
- // * Store the offset at which the MP3 data started; and
- // * Start buffering the frame, as it might contain handy metadata.
-
- // We're now sure this is an MP3 stream.
- mIsMP3 = DEFINITELY_MP3;
-
- // We need to know these to convert the number of frames in the stream
- // to the length of the stream in seconds.
- mSamplesPerSecond = mMP3Parser.GetSampleRate();
- mSamplesPerFrame = mMP3Parser.GetSamplesPerFrame();
-
- // If the stream has a constant bitrate, we should only need the length
- // of the first frame and the length (in bytes) of the stream to
- // estimate the length (in seconds).
- mTotalFrameSize += frameLen;
- mFrameCount++;
-
- // If |mMP3Offset| isn't set then this is the first MP3 frame we have
- // seen in the stream, which is useful for duration estimation.
- if (mMP3Offset > -1) {
- uint16_t skip = frameLen - sizeof(MP3Frame);
- buffer += skip ? skip : 1;
- continue;
- }
-
- // Remember the offset of the MP3 stream.
- // We're at the last byte of an MP3Frame, so MP3 data started
- // sizeof(MP3Frame) - 1 bytes ago.
- mMP3Offset = aStreamOffset
- + (buffer - aBuffer)
- - (sizeof(MP3Frame) - 1);
-
- buffer++;
-
- // If the stream has a variable bitrate, the first frame has metadata
- // we need for duration estimation and seeking. Start buffering it so we
- // can parse it later.
- mFirstFrameEnd = mMP3Offset + frameLen;
- uint64_t currOffset = buffer - aBuffer + aStreamOffset;
- uint64_t copyLen = std::min(mFirstFrameEnd - currOffset,
- (uint64_t)(bufferEnd - buffer));
- mFirstFrame.Append((const char *)buffer, copyLen);
-
- buffer += copyLen;
-
- } else {
- // Nothing to see here. Move along.
- buffer++;
- }
- }
-
- *aOutBytesRead = buffer - aBuffer;
-
- if (mFirstFrameEnd > -1 && mFirstFrameEnd <= aStreamOffset + buffer - aBuffer) {
- // We have our whole first frame. Try to find a VBR header.
- mNumFrames = FindNumVBRFrames(mFirstFrame);
- mFirstFrameEnd = -1;
- }
-
- return NS_OK;
-}
-
-void MP3FrameParser::Parse(const uint8_t* aBuffer, uint32_t aLength, uint64_t aOffset)
-{
- MutexAutoLock mon(mLock);
-
- if (HasExactDuration()) {
- // We know the duration; nothing to do here.
- return;
- }
-
- const uint8_t* buffer = aBuffer;
- int32_t length = aLength;
- uint64_t offset = aOffset;
-
- // Got some data we have seen already. Skip forward to what we need.
- if (aOffset < mOffset) {
- buffer += mOffset - aOffset;
- length -= mOffset - aOffset;
- offset = mOffset;
-
- if (length <= 0) {
- return;
- }
- }
-
- // If there is a discontinuity in the input stream, reset the state of the
- // parsers so we don't get any partial headers.
- if (mOffset < aOffset) {
- if (!mID3Parser.IsParsed()) {
- // Only reset this if it hasn't finished yet.
- mID3Parser.Reset();
- }
-
- if (mFirstFrameEnd > -1) {
- NS_WARNING("Discontinuity in input while buffering first frame.");
- mFirstFrameEnd = -1;
- }
-
- mMP3Parser.Reset();
- }
-
- uint32_t bytesRead = 0;
- if (NS_FAILED(ParseBuffer(buffer,
- length,
- offset,
- &bytesRead))) {
- return;
- }
-
- MOZ_ASSERT(length <= (int)bytesRead, "All bytes should have been consumed");
-
- // Update next data offset
- mOffset = offset + bytesRead;
-
- // If we've parsed lots of data and we still have nothing, just give up.
- // We don't count ID3 headers towards the skipped bytes count, as MP3 files
- // can have massive ID3 sections.
- if (!mID3Parser.IsParsed() && mMP3Offset < 0 &&
- mOffset - mTotalID3Size > MAX_SKIPPED_BYTES) {
- mIsMP3 = NOT_MP3;
- }
-}
-
-int64_t MP3FrameParser::GetDuration()
-{
- MutexAutoLock mon(mLock);
-
- if (!ParsedHeaders() || !mSamplesPerSecond) {
- // Not a single frame decoded yet.
- return -1;
- }
-
- MOZ_ASSERT(mFrameCount > 0 && mTotalFrameSize > 0,
- "Frame parser should have seen at least one MP3 frame of positive length.");
-
- if (!mFrameCount || !mTotalFrameSize) {
- // This should never happen.
- return -1;
- }
-
- double frames;
- if (mNumFrames < 0) {
- // Estimate the number of frames in the stream based on the average frame
- // size and the length of the MP3 file.
- double frameSize = (double)mTotalFrameSize / mFrameCount;
- frames = (double)(mLength - mMP3Offset) / frameSize;
- } else {
- // We know the exact number of frames from the VBR header.
- frames = mNumFrames;
- }
-
- // The duration of each frame is constant over a given stream.
- double usPerFrame = USECS_PER_S * mSamplesPerFrame / mSamplesPerSecond;
-
- return frames * usPerFrame;
-}
-
-int64_t MP3FrameParser::GetMP3Offset()
-{
- MutexAutoLock mon(mLock);
- return mMP3Offset;
-}
-
-bool MP3FrameParser::ParsedHeaders()
-{
- // We have seen both the beginning and the end of the first MP3 frame in the
- // stream.
- return mMP3Offset > -1 && mFirstFrameEnd < 0;
-}
-
-bool MP3FrameParser::HasExactDuration()
-{
- return ParsedHeaders() && mNumFrames > -1;
-}
-
-bool MP3FrameParser::NeedsData()
-{
- // If we don't know the duration exactly then either:
- // - we're still waiting for a VBR header; or
- // - we look at all frames to constantly update our duration estimate.
- return IsMP3() && !HasExactDuration();
-}
-
-} // namespace mozilla
diff --git a/dom/media/MP3FrameParser.h b/dom/media/MP3FrameParser.h
deleted file mode 100644
index d2ba791fd..000000000
--- a/dom/media/MP3FrameParser.h
+++ /dev/null
@@ -1,219 +0,0 @@
-/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* vim:set ts=2 sw=2 sts=2 et cindent: */
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-#ifndef MP3FrameParser_h
-#define MP3FrameParser_h
-
-#include <stdint.h>
-
-#include "mozilla/Mutex.h"
-#include "nsString.h"
-#include "Intervals.h"
-
-namespace mozilla {
-
-// Simple parser to tell whether we've found an ID3 header and how long it is,
-// so that we can skip it.
-// XXX maybe actually parse this stuff?
-class ID3Parser
-{
-public:
- ID3Parser();
-
- void Reset();
- bool ParseChar(char ch);
- bool IsParsed() const;
- uint32_t GetHeaderLength() const;
-
-private:
- uint32_t mCurrentChar;
- uint8_t mVersion;
- uint8_t mFlags;
- uint32_t mHeaderLength;
-};
-
-struct MP3Frame {
- uint16_t mSync1 : 8; // Always all set
- uint16_t mProtected : 1; // Ignored
- uint16_t mLayer : 2;
- uint16_t mVersion : 2;
- uint16_t mSync2 : 3; // Always all set
- uint16_t mPrivate : 1; // Ignored
- uint16_t mPad : 1;
- uint16_t mSampleRate : 2; // Index into mpeg_srates above
- uint16_t mBitrate : 4; // Index into mpeg_bitrates above
-
- uint16_t CalculateLength();
-};
-
-// Buffering parser for MP3 frames.
-class MP3Parser
-{
-public:
- MP3Parser();
-
- // Forget all data the parser has seen so far.
- void Reset();
-
- // Parse the given byte. If we have found a frame header, return the length of
- // the frame.
- uint16_t ParseFrameLength(uint8_t ch);
-
- // Get the sample rate from the current header.
- uint32_t GetSampleRate();
-
- // Get the number of samples per frame.
- uint32_t GetSamplesPerFrame();
-
-private:
- uint32_t mCurrentChar;
- union {
- uint8_t mRaw[3];
- MP3Frame mFrame;
- } mData;
-};
-
-
-// A description of the MP3 format and its extensions is available at
-//
-// http://www.codeproject.com/Articles/8295/MPEG-Audio-Frame-Header
-//
-// The data in MP3 streams is split into small frames, with each frame
-// containing a fixed number of samples. The duration of a frame depends
-// on the frame's bit rate and sample rate. Both values can vary among
-// frames, so it is necessary to examine each individual frame of an MP3
-// stream to calculate the stream's overall duration.
-//
-// The MP3 frame parser extracts information from an MP3 data stream. It
-// accepts a range of frames of an MP3 stream as input, and parses all
-// frames for their duration. Callers can query the stream's overall
-// duration from the parser.
-//
-// Call the methods NotifyDataArrived or Parse to add new data. If you added
-// information for a certain stream position, you cannot go back to previous
-// positions. The parser will simply ignore the input. If you skip stream
-// positions, the duration of the related MP3 frames will be estimated from
-// the stream's average.
-//
-// The method GetDuration returns calculated duration of the stream, including
-// estimates for skipped ranges.
-//
-// All public methods are thread-safe.
-
-class MP3FrameParser
-{
-public:
- explicit MP3FrameParser(int64_t aLength=-1);
-
- bool IsMP3() {
- MutexAutoLock mon(mLock);
- return mIsMP3 != NOT_MP3;
- }
-
- void Parse(const uint8_t* aBuffer, uint32_t aLength, uint64_t aStreamOffset);
-
- // Returns the duration, in microseconds. If the entire stream has not
- // been parsed yet, this is an estimate based on the bitrate of the
- // frames parsed so far.
- int64_t GetDuration();
-
- // Returns the offset of the first MP3 frame in the stream, or -1 of
- // no MP3 frame has been detected yet.
- int64_t GetMP3Offset();
-
- // Returns true if we've seen the whole first frame of the MP3 stream, and
- // therefore can make an estimate on the stream duration.
- // Otherwise, returns false.
- bool ParsedHeaders();
-
- // Returns true if we know the exact duration of the MP3 stream;
- // false otherwise.
- bool HasExactDuration();
-
- // Returns true if the parser needs more data for duration estimation.
- bool NeedsData();
- // Assign the total lenght of this mp3 stream
- void SetLength(int64_t aLength) {
- MutexAutoLock mon(mLock);
- mLength = aLength;
- }
-private:
-
- // Parses aBuffer, starting at offset 0. Returns the number of bytes
- // parsed, relative to the start of the buffer. Note this may be
- // greater than aLength if the headers in the buffer indicate that
- // the frame or ID3 tag extends outside of aBuffer. Returns failure
- // if too many non-MP3 bytes are parsed.
- nsresult ParseBuffer(const uint8_t* aBuffer,
- uint32_t aLength,
- int64_t aStreamOffset,
- uint32_t* aOutBytesRead);
-
- // A low-contention lock for protecting the parser results
- Mutex mLock;
-
- // ID3 header parser. Keeps state between reads in case the header falls
- // in between.
- ID3Parser mID3Parser;
-
- // MP3 frame header parser.
- MP3Parser mMP3Parser;
-
- // If we read |MAX_SKIPPED_BYTES| from the stream without finding any MP3
- // frames, we give up and report |NOT_MP3|. Here we track the cumulative size
- // of any ID3 headers we've seen so big ID3 sections aren't counted towards
- // skipped bytes.
- uint32_t mTotalID3Size;
-
- // All fields below are protected by mLock
-
- // We keep stats on the size of all the frames we've seen, as well as how many
- // so that we can estimate the duration of the rest of the stream.
- uint64_t mTotalFrameSize;
- uint64_t mFrameCount;
-
- // Offset of the last data parsed. This is the end offset of the last data
- // block parsed, so it's the start offset we expect to get on the next
- // call to Parse().
- uint64_t mOffset;
-
- // Total length of the stream in bytes.
- int64_t mLength;
-
- // Offset of first MP3 frame in the bitstream. Has value -1 until the
- // first MP3 frame is found.
- int64_t mMP3Offset;
-
- // The exact number of frames in this stream, if we know it. -1 otherwise.
- int64_t mNumFrames;
-
- // Number of audio samples per second and per frame. Fixed through the whole
- // file. If we know these variables as well as the number of frames in the
- // file, we can get an exact duration for the stream.
- uint16_t mSamplesPerSecond;
- uint16_t mSamplesPerFrame;
-
- // If the MP3 has a variable bitrate, then there *should* be metadata about
- // the encoding in the first frame. We buffer the first frame here.
- nsCString mFirstFrame;
-
- // While we are reading the first frame, this is the stream offset of the
- // last byte of that frame. -1 at all other times.
- int64_t mFirstFrameEnd;
-
- enum eIsMP3 {
- MAYBE_MP3, // We're giving the stream the benefit of the doubt...
- DEFINITELY_MP3, // We've hit at least one ID3 tag or MP3 frame.
- NOT_MP3 // Not found any evidence of the stream being MP3.
- };
-
- eIsMP3 mIsMP3;
-
-};
-
-} // namespace mozilla
-
-#endif
diff --git a/dom/media/moz.build b/dom/media/moz.build
index b3db05af1..772f27b35 100644
--- a/dom/media/moz.build
+++ b/dom/media/moz.build
@@ -127,7 +127,6 @@ EXPORTS += [
'MediaTrackList.h',
'MP3Decoder.h',
'MP3Demuxer.h',
- 'MP3FrameParser.h',
'NextFrameSeekTask.h',
'nsIDocumentActivity.h',
'PrincipalChangeObserver.h',
@@ -236,7 +235,6 @@ UNIFIED_SOURCES += [
'MediaTrackList.cpp',
'MP3Decoder.cpp',
'MP3Demuxer.cpp',
- 'MP3FrameParser.cpp',
'NextFrameSeekTask.cpp',
'QueueObject.cpp',
'SeekJob.cpp',
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-27 18:01:43 +0000